Methods

Reperfusion is defined as the relative Tmax >6s change (% of baseline).
Surrogates for good collateral flow in this study are:
* Degree of reperfusion in non-recanalizers
* The hypoperfusion intensity ration (HIR) at baseline (lower is better), defined according to:
Bang, O. Y. et al. (2008) ‘Determinants of the distribution and severity of hypoperfusion in patients with ischemic stroke.’, Neurology
* The modified ASITN/SIR Collateral Flow Grading System (adapted for DSC-MRI, aka “Higashida score”), according to:
Campbell BC V, Christensen S, Tress BM, Churilov L, Desmond PM, Parsons MW, Alan Barber P, Levi CR, Bladin C, Donnan GA, Davis SM (2013) Failure of collateral blood flow is associated with infarct growth in ischemic stroke. J Cereb Blood Flow Metab and dichotomized into good (3-4) and poor (0-2) according to: Galinovic I, Kochova E, Khalil A, Villringer K, Piper SK, Fiebach JB (2018) The ratio between cerebral blood flow and Tmax predicts the quality of collaterals in acute ischemic stroke. PLoS One 13:e0190811

The outcome measures in this study are:
* Extent of reperfusion - relative Tmax >6s change (%)
* Modified Rankin Scale at Day 90
* Absolute infarct growth on DWI between days 1 and 2 (mL)
* Absolute infarct growth between days 1 (DWI) and 5 (FLAIR) (mL)

All regression analyses are performed using a robust GLM (“High Breakdown And High Efficiency Robust Linear Regression”) using the R function “lmrob” from the “robustbase” package.
Citation of package:
Martin Maechler, Peter Rousseeuw, Christophe Croux, Valentin Todorov, Andreas Ruckstuhl, Matias Salibian-Barrera, Tobias Verbeke, Manuel Koller, Eduardo L. T. Conceicao and Maria Anna di Palma (2018). robustbase: Basic Robust Statistics R package version 0.93-0. URL http://CRAN.R-project.org/package=robustbase
Citation of robust GLM:
Yohai, V. J. (1987). High breakdown-point and high efficiency robust estimates for regression. The Annals of Statistics, 642-656.

For visualization (not analysis) purposes, outliers are not shown on the boxplots.

Power analysis:

Sample size needed to detect a minimum effect size (R2/1-R2) of 0.1 at significance level of 0.05 and power of 0.8 with 8 predictors (including interactions) = 158. Performed with the R package “pwr”.
Citation of package:
Stephane Champely (2018). pwr: Basic Functions for Power Analysis. R package version 1.2-2. https://CRAN.R-project.org/package=pwr

Summary of main results

  • Higashida score and recanalization are independent predictors of reperfusion. See Predictors of extent of reperfusion
  • Collateral flow (HIR or Higashida score) does not predict reperfusion in full recanalizers. See [Predictors of extent of reperfusion in full recanalizers]
  • Collateral flow (HIR or Higashida score) does not predict reperfusion in non-recanalizers. See [Predictors of extent of reperfusion in non-recanalizers]
  • Higashida score independently predicts reperfusion in partial recanalizers. See [Predictors of extent of reperfusion in partial recanalizers]
  • NIHSS on admission and recanalization independently predict 90 day mRS. Collateral flow and reperfusion do not. See Predictors of clinical outcome
  • Collateral flow (both Higashida and HIR), NIHSS on admission, and reperfusion in partial recanalizers independently predict early infarct growth (D1 - D2). See Predictors of absolute infarct growth (D1 - D2)
  • Collateral flow (both Higashida and HIR), NIHSS on admission, and reperfusion in partial recanalizers independently predict late infarct growth (D1 - D5). See Predictors of absolute infarct growth (D1 - D5)

Descriptive statistics

## Factors are dropped from the summary
N Missing Mean SD Min Q1 Median Q3 Max
ID 186 0 156.76 96.20 2.00 71.00 154.50 242.00 323.00
age 186 0 71.72 13.23 23.00 66.00 74.00 82.00 93.00
TSI 186 0 6.97 6.81 0.00 1.50 3.55 12.10 24.00
NIHSS_ad 186 0 8.28 6.33 0.00 3.00 6.00 13.00 25.00
NIHSS_dis 185 1 4.39 5.66 0.00 0.00 2.00 6.00 29.00
mRS_ad 176 10 3.03 1.47 0.00 2.00 3.00 4.00 5.00
mRS_dis 173 13 2.19 1.64 0.00 1.00 2.00 4.00 6.00
mRS_d90 149 37 2.30 1.92 0.00 1.00 2.00 4.00 6.00
DWIvol_d1 186 0 15.26 27.48 0.00 0.99 5.40 18.55 231.36
DWIvol_d2 186 0 31.18 49.31 0.00 3.07 12.39 39.64 324.01
Tmax_vol_d1 186 0 45.47 49.77 0.00 11.00 26.60 67.00 258.63
Tmax_vol_d2 186 0 26.83 85.47 0.00 1.00 7.00 27.50 1094.00
DWIgrowth 186 0 15.91 28.08 -1.34 0.72 5.28 14.74 178.68
rel_DWIgrowth 186 0 357.66 1268.39 -100.00 30.46 72.54 210.90 11561.11
Tmax_change 186 0 -23.94 42.72 -258.63 -37.00 -9.50 -1.00 104.80
relTmax_change 186 0 -29.35 143.98 -100.00 -95.56 -57.30 -7.69 1433.33
mismatch_vol 186 0 30.21 47.59 -119.36 0.84 16.76 53.16 253.40
infarct_growth_D5FLAIR 141 45 26.87 43.08 -3.68 1.97 8.50 29.69 222.72
FLAIR_d5_vol 141 45 41.57 57.20 0.01 5.90 18.50 55.50 300.40
Tmax_D1_.2_volume 186 0 83.28 60.82 1.05 33.30 72.75 120.61 317.11
Tmax_D1_.4_volume 186 0 64.04 57.58 0.14 19.03 46.88 93.02 317.11
Tmax_D1_.8_volume 186 0 27.50 34.79 0.00 2.82 12.70 38.68 172.25
Tmax_D2_.2_volume 186 0 48.02 53.07 0.00 8.02 30.91 62.36 281.54
Tmax_D2_.4_volume 186 0 32.84 44.49 0.00 2.41 16.44 40.61 226.83
Tmax_D2_.8_volume 186 0 11.60 21.45 0.00 0.08 1.62 14.76 130.90
HIR1 186 0 0.27 0.24 0.00 0.07 0.23 0.42 1.00
HIR2 178 8 0.18 0.24 0.00 0.01 0.07 0.29 1.00
Tmax_D1_.6_volume 186 0 45.47 49.77 0.00 11.00 26.60 67.00 258.63
Tmax_D2_.6_volume 186 0 26.83 85.47 0.00 1.00 7.00 27.50 1094.00
Tmax_6_reperf_abs 186 0 18.64 84.23 -966.10 1.00 9.00 37.00 258.63
Tmax_6_reperf_rel 180 6 26.05 157.55 -1433.33 11.09 66.18 96.09 100.00 
##                     Level     N    %
## 1  higashida_D1         0     4  2.2
## 2                       1    31 16.7
## 3                       2    50 26.9
## 4                       3    49 26.3
## 5                       4    51 27.4
## 6                     NaN     0  0.0
## 7               <Missing>     1  0.5
## 8  higashida_D2         0     3  1.6
## 9                       1    22 11.8
## 10                      2    38 20.4
## 11                      3    39 21.0
## 12                      4    81 43.5
## 13                    NaN     0  0.0
## 14              <Missing>     3  1.6
## 15        Rekan      None    67 36.0
## 16                Partial    64 34.4
## 17                   Full    55 29.6
## 18  circulation  Anterior   142 76.3
## 19              Posterior    44 23.7
## 20          sex    Female    79 42.5
## 21                   Male   107 57.5
## 22       iv_tPR        No   106 57.0
## 23                    Yes    80 43.0
Plot showing the change in Higashida scores over time for each patient.

Predictors of extent of reperfusion

Dependent variable:
Tmax_6_reperf_rel
(1) (2) (3) (4)
NIHSS_ad -0.605 (0.606) -0.248 (0.563) -0.225 (0.605) 0.257 (0.536)
t = -0.998 t = -0.440 t = -0.372 t = 0.479
p = 0.320 p = 0.661 p = 0.711 p = 0.633
iv_tPRYes 16.778** (7.372) 6.089 (7.200) 5.314 (7.271) 5.530 (6.700)
t = 2.276 t = 0.846 t = 0.731 t = 0.825
p = 0.025 p = 0.399 p = 0.466 p = 0.411
RekanPartial 26.774*** (7.780) 22.873* (12.077) 27.384*** (9.714)
t = 3.441 t = 1.894 t = 2.819
p = 0.001 p = 0.060 p = 0.006
RekanFull 43.999*** (8.495) 31.011** (13.239) 33.681*** (10.641)
t = 5.179 t = 2.342 t = 3.165
p = 0.00000 p = 0.021 p = 0.002
HIR1 -21.505 (25.723)
t = -0.836
p = 0.405
higashida_D1_binPoor -24.774** (10.317)
t = -2.401
p = 0.018
circulationPosterior -21.023** (8.773) -15.293* (8.088) -14.228* (8.132) -11.229 (7.501)
t = -2.396 t = -1.891 t = -1.750 t = -1.497
p = 0.018 p = 0.061 p = 0.082 p = 0.137
RekanPartial:HIR1 14.252 (33.521)
t = 0.425
p = 0.672
RekanFull:HIR1 43.918 (36.192)
t = 1.213
p = 0.227
RekanPartial:higashida_D1_binPoor -12.396 (14.319)
t = -0.866
p = 0.388
RekanFull:higashida_D1_binPoor 21.163 (14.861)
t = 1.424
p = 0.157
Constant 58.155*** (7.129) 36.180*** (7.879) 42.089*** (9.968) 45.000*** (8.405)
t = 8.158 t = 4.592 t = 4.222 t = 5.354
p = 0.000 p = 0.00001 p = 0.00004 p = 0.00000
Observations 180 180 180 180
R2 0.063 0.199 0.200 0.280
Adjusted R2 0.047 0.176 0.162 0.246
Residual Std. Error 46.630 (df = 176) 42.332 (df = 174) 42.418 (df = 171) 39.082 (df = 171)
Note: p<0.1; p<0.05; p<0.01
1 vs 2
Statistic N Mean St. Dev. Min Pctl(25) Pctl(75) Max
pseudoDf 2 175.000 1.414 174 174.5 175.5 176
Test.Stat 1 27.943 27.943 27.943 27.943 27.943
Df 1 2.000 2.000 2.000 2.000 2.000
Pr(> chisq) 1 0.00000 0.00000 0.00000 0.00000 0.00000
1 vs 3
Statistic N Mean St. Dev. Min Pctl(25) Pctl(75) Max
pseudoDf 2 173.500 3.536 171 172.2 174.8 176
Test.Stat 1 28.640 28.640 28.640 28.640 28.640
Df 1 5.000 5.000 5.000 5.000 5.000
Pr(> chisq) 1 0.00003 0.00003 0.00003 0.00003 0.00003
1 vs 4
Statistic N Mean St. Dev. Min Pctl(25) Pctl(75) Max
pseudoDf 2 173.500 3.536 171 172.2 174.8 176
Test.Stat 1 50.570 50.570 50.570 50.570 50.570
Df 1 5.000 5.000 5.000 5.000 5.000
Pr(> chisq) 1 0.000 0.000 0.000 0.000 0.000
Predictors of extent of reperfusion
HIR Higashida
NIHSS on admission -0.225 (0.605) 0.257 (0.536)
t = -0.372 t = 0.479
p = 0.711 p = 0.633
IV tPA (yes) 5.314 (7.271) 5.530 (6.700)
t = 0.731 t = 0.825
p = 0.466 p = 0.411
Recanalization (partial) 22.873* (12.077) 27.384*** (9.714)
t = 1.894 t = 2.819
p = 0.060 p = 0.006
Recanalization (full) 31.011** (13.239) 33.681*** (10.641)
t = 2.342 t = 3.165
p = 0.021 p = 0.002
HIR -21.505 (25.723)
t = -0.836
p = 0.405
Higashida (poor) -24.774** (10.317)
t = -2.401
p = 0.018
Circulation (posterior) -14.228* (8.132) -11.229 (7.501)
t = -1.750 t = -1.497
p = 0.082 p = 0.137
Recanalization (partial)*HIR 14.252 (33.521)
t = 0.425
p = 0.672
Recanalization (full)*HIR 43.918 (36.192)
t = 1.213
p = 0.227
Recanalization (partial)*Higashida (poor) -12.396 (14.319)
t = -0.866
p = 0.388
Recanalization (full)*Higashida (poor) 21.163 (14.861)
t = 1.424
p = 0.157
Constant 42.089*** (9.968) 45.000*** (8.405)
t = 4.222 t = 5.354
p = 0.00004 p = 0.00000
Observations 180 180
R2 0.200 0.280
Adjusted R2 0.162 0.246
Residual Std. Error (df = 171) 42.418 39.082
Note: p<0.1; p<0.05; p<0.01

Predictors of clinical outcome

Dependent variable:
mRS_d90
(1) (2) (3) (4) (5) (6)
NIHSS_ad 0.162*** (0.026) 0.165*** (0.026) 0.171*** (0.025)
t = 6.281 t = 6.378 t = 6.753
p = 0.000 p = 0.000 p = 0.000
iv_tPRYes -0.526* (0.305) -0.559* (0.307) -0.565* (0.314)
t = -1.723 t = -1.820 t = -1.798
p = 0.088 p = 0.071 p = 0.075
RekanPartial -0.979** (0.480) -0.683 (0.432) -0.923* (0.480)
t = -2.038 t = -1.581 t = -1.921
p = 0.044 p = 0.117 p = 0.057
RekanFull -1.572*** (0.513) -1.266*** (0.451) -1.299** (0.550)
t = -3.066 t = -2.809 t = -2.364
p = 0.003 p = 0.006 p = 0.020
HIR1 2.110*** (0.722) 0.869 (1.078)
t = 2.922 t = 0.806
p = 0.005 p = 0.422
circulationPosterior 0.372 (0.313) 0.401 (0.313) 0.383 (0.319)
t = 1.188 t = 1.281 t = 1.200
p = 0.237 p = 0.203 p = 0.233
RekanPartial:HIR1 -0.307 (1.432)
t = -0.214
p = 0.831
RekanFull:HIR1 0.596 (1.553)
t = 0.384
p = 0.702
RekanPartial:higashida_D1_binPoor -0.725 (0.652)
t = -1.113
p = 0.268
RekanFull:higashida_D1_binPoor -0.151 (0.672)
t = -0.225
p = 0.823
higashida_D1_binPoor 1.035*** (0.328) 0.631 (0.464)
t = 3.152 t = 1.361
p = 0.002 p = 0.176
RekanPartial:Tmax_6_reperf_rel -0.003 (0.006)
t = -0.418
p = 0.677
RekanFull:Tmax_6_reperf_rel -0.002 (0.006)
t = -0.312
p = 0.756
Tmax_6_reperf_rel -0.003 (0.002) -0.0004 (0.002)
t = -1.568 t = -0.278
p = 0.120 p = 0.782
Constant 1.695*** (0.248) 1.664*** (0.379) 1.800*** (0.215) 1.539*** (0.358) 2.408*** (0.184) 1.902*** (0.322)
t = 6.845 t = 4.391 t = 8.385 t = 4.302 t = 13.104 t = 5.901
p = 0.000 p = 0.00003 p = 0.000 p = 0.00004 p = 0.000 p = 0.00000
Observations 149 149 149 149 144 144
R2 0.057 0.369 0.066 0.368 0.018 0.362
Adjusted R2 0.051 0.333 0.059 0.332 0.011 0.324
Residual Std. Error 1.959 (df = 147) 1.592 (df = 140) 1.946 (df = 147) 1.594 (df = 140) 1.997 (df = 142) 1.600 (df = 135)
Note: p<0.1; p<0.05; p<0.01
1 vs 2
Statistic N Mean St. Dev. Min Pctl(25) Pctl(75) Max
pseudoDf 2 143.500 4.950 140 141.8 145.2 147
Test.Stat 1 66.264 66.264 66.264 66.264 66.264
Df 1 7.000 7.000 7.000 7.000 7.000
Pr(> chisq) 1 0.000 0.000 0.000 0.000 0.000
1 vs 3
Statistic N Mean St. Dev. Min Pctl(25) Pctl(75) Max
pseudoDf 2 143.500 4.950 140 141.8 145.2 147
Test.Stat 1 64.648 64.648 64.648 64.648 64.648
Df 1 7.000 7.000 7.000 7.000 7.000
Pr(> chisq) 1 0.000 0.000 0.000 0.000 0.000
1 vs 4
Statistic N Mean St. Dev. Min Pctl(25) Pctl(75) Max
pseudoDf 2 138.500 4.950 135 136.8 140.2 142
Test.Stat 1 70.073 70.073 70.073 70.073 70.073
Df 1 7.000 7.000 7.000 7.000 7.000
Pr(> chisq) 1 0.000 0.000 0.000 0.000 0.000
Predictors of long-term clinical outcome (mRS day 90)
HIR Higashida Reperfusion
NIHSS on admission 0.162*** (0.026) 0.165*** (0.026) 0.171*** (0.025)
t = 6.281 t = 6.378 t = 6.753
p = 0.000 p = 0.000 p = 0.000
IV tPA (yes) -0.526* (0.305) -0.559* (0.307) -0.565* (0.314)
t = -1.723 t = -1.820 t = -1.798
p = 0.088 p = 0.071 p = 0.075
Recanalization (partial) -0.979** (0.480) -0.683 (0.432) -0.923* (0.480)
t = -2.038 t = -1.581 t = -1.921
p = 0.044 p = 0.117 p = 0.057
Recanalization (full) -1.572*** (0.513) -1.266*** (0.451) -1.299** (0.550)
t = -3.066 t = -2.809 t = -2.364
p = 0.003 p = 0.006 p = 0.020
HIR 0.869 (1.078)
t = 0.806
p = 0.422
Higashida (poor) 0.631 (0.464)
t = 1.361
p = 0.176
Reperfusion -0.0004 (0.002)
t = -0.278
p = 0.782
Circulation (posterior) 0.372 (0.313) 0.401 (0.313) 0.383 (0.319)
t = 1.188 t = 1.281 t = 1.200
p = 0.237 p = 0.203 p = 0.233
Recanalization (partial)*HIR -0.307 (1.432)
t = -0.214
p = 0.831
Recanalization (full)*HIR 0.596 (1.553)
t = 0.384
p = 0.702
Recanalization (partial)*Higashida (poor) -0.725 (0.652)
t = -1.113
p = 0.268
Recanalization (full)*Higashida (poor) -0.151 (0.672)
t = -0.225
p = 0.823
Recanalization (partial)*Reperfusion -0.003 (0.006)
t = -0.418
p = 0.677
Recanalization (full)*Reperfusion -0.002 (0.006)
t = -0.312
p = 0.756
Constant 1.664*** (0.379) 1.539*** (0.358) 1.902*** (0.322)
t = 4.391 t = 4.302 t = 5.901
p = 0.00003 p = 0.00004 p = 0.00000
Observations 149 149 144
R2 0.369 0.368 0.362
Adjusted R2 0.333 0.332 0.324
Residual Std. Error 1.592 (df = 140) 1.594 (df = 140) 1.600 (df = 135)
Note: p<0.1; p<0.05; p<0.01

Predictors of absolute infarct growth (D1 - D2)

Dependent variable:
DWIgrowth
(1) (2) (3) (4) (5) (6)
NIHSS_ad 0.413*** (0.108) 0.405*** (0.100) 0.615*** (0.120)
t = 3.820 t = 4.032 t = 5.132
p = 0.0002 p = 0.0001 p = 0.00000
iv_tPRYes -0.067 (1.294) -0.545 (1.233) 0.630 (1.469)
t = -0.052 t = -0.442 t = 0.429
p = 0.959 p = 0.659 p = 0.669
RekanPartial -1.475 (1.990) 0.661 (1.645) 2.073 (1.482) 1.228 (1.628)
t = -0.741 t = 0.402 t = 1.398 t = 0.755
p = 0.460 p = 0.689 p = 0.164 p = 0.452
RekanFull 0.232 (2.093) 0.986 (1.775) 1.086 (2.185) 0.114 (2.497)
t = 0.111 t = 0.556 t = 0.497 t = 0.046
p = 0.912 p = 0.580 p = 0.620 p = 0.964
HIR1 13.157*** (2.364) 12.810*** (4.847)
t = 5.566 t = 2.643
p = 0.00000 p = 0.009
higashida_D1_binPoor 5.223*** (0.978) 7.024*** (1.918)
t = 5.340 t = 3.662
p = 0.00000 p = 0.0004
Tmax_6_reperf_rel 0.003 (0.008) -0.002 (0.008)
t = 0.352 t = -0.245
p = 0.726 p = 0.807
circulationPosterior 0.169 (1.178) 1.114 (1.349) -0.055 (1.094) 0.910 (1.269) -0.451 (1.384) 1.400 (1.558)
t = 0.143 t = 0.826 t = -0.051 t = 0.717 t = -0.326 t = 0.898
p = 0.887 p = 0.410 p = 0.960 p = 0.475 p = 0.745 p = 0.371
RekanPartial:HIR1 2.420 (6.395)
t = 0.378
p = 0.706
RekanFull:HIR1 -4.650 (6.539)
t = -0.711
p = 0.478
RekanPartial:higashida_D1_binPoor -2.160 (2.725)
t = -0.792
p = 0.430
RekanFull:higashida_D1_binPoor -3.600 (2.643)
t = -1.362
p = 0.175
RekanPartial:Tmax_6_reperf_rel -0.033*** (0.009) -0.025** (0.010)
t = -3.691 t = -2.554
p = 0.0003 p = 0.012
RekanFull:Tmax_6_reperf_rel -0.012 (0.024) -0.012 (0.026)
t = -0.509 t = -0.478
p = 0.612 p = 0.634
Constant 2.526*** (0.840) 0.569 (1.573) 3.381*** (0.682) 0.623 (1.354) 5.990*** (1.158) 2.041 (1.537)
t = 3.006 t = 0.361 t = 4.957 t = 0.461 t = 5.173 t = 1.328
p = 0.004 p = 0.719 p = 0.00001 p = 0.646 p = 0.00000 p = 0.186
Observations 186 186 186 186 180 180
R2 0.135 0.222 0.128 0.212 0.176 0.258
Adjusted R2 0.126 0.187 0.118 0.176 0.147 0.223
Residual Std. Error 7.129 (df = 183) 7.554 (df = 177) 6.654 (df = 183) 7.267 (df = 177) 8.456 (df = 173) 8.693 (df = 171)
Note: p<0.1; p<0.05; p<0.01
1 vs 2
Statistic N Mean St. Dev. Min Pctl(25) Pctl(75) Max
pseudoDf 2 180.000 4.243 177 178.5 181.5 183
Test.Stat 1 16.646 16.646 16.646 16.646 16.646
Df 1 6.000 6.000 6.000 6.000 6.000
Pr(> chisq) 1 0.011 0.011 0.011 0.011 0.011
1 vs 3
Statistic N Mean St. Dev. Min Pctl(25) Pctl(75) Max
pseudoDf 2 180.000 4.243 177 178.5 181.5 183
Test.Stat 1 19.266 19.266 19.266 19.266 19.266
Df 1 6.000 6.000 6.000 6.000 6.000
Pr(> chisq) 1 0.004 0.004 0.004 0.004 0.004
1 vs 4
Statistic N Mean St. Dev. Min Pctl(25) Pctl(75) Max
pseudoDf 2 172.000 1.414 171 171.5 172.5 173
Test.Stat 1 29.497 29.497 29.497 29.497 29.497
Df 1 2.000 2.000 2.000 2.000 2.000
Pr(> chisq) 1 0.00000 0.00000 0.00000 0.00000 0.00000
Predictors of early infarct growth
HIR Higashida Reperfusion
NIHSS on admission 0.413*** (0.108) 0.405*** (0.100) 0.615*** (0.120)
t = 3.820 t = 4.032 t = 5.132
p = 0.0002 p = 0.0001 p = 0.00000
IV tPA (yes) -0.067 (1.294) -0.545 (1.233) 0.630 (1.469)
t = -0.052 t = -0.442 t = 0.429
p = 0.959 p = 0.659 p = 0.669
Recanalization (partial) -1.475 (1.990) 0.661 (1.645) 1.228 (1.628)
t = -0.741 t = 0.402 t = 0.755
p = 0.460 p = 0.689 p = 0.452
Recanalization (full) 0.232 (2.093) 0.986 (1.775) 0.114 (2.497)
t = 0.111 t = 0.556 t = 0.046
p = 0.912 p = 0.580 p = 0.964
HIR 12.810*** (4.847)
t = 2.643
p = 0.009
Higashida (poor) 7.024*** (1.918)
t = 3.662
p = 0.0004
Reperfusion -0.002 (0.008)
t = -0.245
p = 0.807
Circulation (posterior) 1.114 (1.349) 0.910 (1.269) 1.400 (1.558)
t = 0.826 t = 0.717 t = 0.898
p = 0.410 p = 0.475 p = 0.371
Recanalization (partial)*HIR 2.420 (6.395)
t = 0.378
p = 0.706
Recanalization (full)*HIR -4.650 (6.539)
t = -0.711
p = 0.478
Recanalization (partial)*Higashida (poor) -2.160 (2.725)
t = -0.792
p = 0.430
Recanalization (full)*Higashida (poor) -3.600 (2.643)
t = -1.362
p = 0.175
Recanalization (partial)*Reperfusion -0.025** (0.010)
t = -2.554
p = 0.012
Recanalization (full)*Reperfusion -0.012 (0.026)
t = -0.478
p = 0.634
Constant 0.569 (1.573) 0.623 (1.354) 2.041 (1.537)
t = 0.361 t = 0.461 t = 1.328
p = 0.719 p = 0.646 p = 0.186
Observations 186 186 180
R2 0.222 0.212 0.258
Adjusted R2 0.187 0.176 0.223
Residual Std. Error 7.554 (df = 177) 7.267 (df = 177) 8.693 (df = 171)
Note: p<0.1; p<0.05; p<0.01

Predictors of absolute infarct growth (D1 - D5)

Dependent variable:
infarct_growth_D5FLAIR
(1) (2) (3) (4) (5) (6)
NIHSS_ad 1.146*** (0.253) 1.064*** (0.238) 1.536*** (0.271)
t = 4.530 t = 4.468 t = 5.671
p = 0.00002 p = 0.00002 p = 0.00000
iv_tPRYes 0.052 (2.774) 0.557 (2.688) 0.652 (3.062)
t = 0.019 t = 0.207 t = 0.213
p = 0.986 p = 0.837 p = 0.832
RekanPartial -1.135 (4.278) -0.057 (3.656) 10.059*** (3.475) 6.325* (3.411)
t = -0.265 t = -0.016 t = 2.894 t = 1.854
p = 0.792 p = 0.988 p = 0.005 p = 0.067
RekanFull -0.028 (4.646) -0.262 (3.923) -1.055 (5.183) -2.898 (5.167)
t = -0.006 t = -0.067 t = -0.203 t = -0.561
p = 0.996 p = 0.947 p = 0.840 p = 0.576
HIR1 23.701*** (5.822) 17.653* (10.182)
t = 4.071 t = 1.734
p = 0.0001 p = 0.086
higashida_D1_binPoor 10.572*** (2.429) 9.345** (4.001)
t = 4.352 t = 2.335
p = 0.00003 p = 0.022
Tmax_6_reperf_rel 0.014 (0.017) 0.004 (0.016)
t = 0.859 t = 0.271
p = 0.393 p = 0.787
circulationPosterior -1.105 (2.822) 1.295 (2.850) -1.399 (2.668) 0.503 (2.717) -2.640 (3.236) 1.360 (3.210)
t = -0.392 t = 0.454 t = -0.524 t = 0.185 t = -0.816 t = 0.424
p = 0.696 p = 0.651 p = 0.601 p = 0.854 p = 0.417 p = 0.673
RekanPartial:HIR1 2.813 (13.503)
t = 0.208
p = 0.836
RekanFull:HIR1 -10.734 (14.885)
t = -0.721
p = 0.473
RekanPartial:higashida_D1_binPoor 4.994 (5.807)
t = 0.860
p = 0.392
RekanFull:higashida_D1_binPoor -4.928 (5.757)
t = -0.856
p = 0.394
RekanPartial:Tmax_6_reperf_rel -0.117*** (0.019) -0.099*** (0.019)
t = -6.084 t = -5.302
p = 0.000 p = 0.00000
RekanFull:Tmax_6_reperf_rel -0.017 (0.055) 0.002 (0.053)
t = -0.309 t = 0.043
p = 0.758 p = 0.966
Constant 6.649*** (2.082) 1.133 (3.254) 7.762*** (1.723) 1.265 (2.969) 12.834*** (2.733) 2.635 (3.235)
t = 3.193 t = 0.348 t = 4.504 t = 0.426 t = 4.697 t = 0.814
p = 0.002 p = 0.729 p = 0.00002 p = 0.671 p = 0.00001 p = 0.417
Observations 141 141 141 141 138 138
R2 0.115 0.257 0.129 0.301 0.490 0.579
Adjusted R2 0.102 0.212 0.116 0.259 0.466 0.552
Residual Std. Error 14.323 (df = 138) 14.158 (df = 132) 13.614 (df = 138) 13.483 (df = 132) 16.765 (df = 131) 16.086 (df = 129)
Note: p<0.1; p<0.05; p<0.01
1 vs 2
Statistic N Mean St. Dev. Min Pctl(25) Pctl(75) Max
pseudoDf 2 135.000 4.243 132 133.5 136.5 138
Test.Stat 1 24.668 24.668 24.668 24.668 24.668
Df 1 6.000 6.000 6.000 6.000 6.000
Pr(> chisq) 1 0.0004 0.0004 0.0004 0.0004 0.0004
1 vs 3
Statistic N Mean St. Dev. Min Pctl(25) Pctl(75) Max
pseudoDf 2 135.000 4.243 132 133.5 136.5 138
Test.Stat 1 31.061 31.061 31.061 31.061 31.061
Df 1 6.000 6.000 6.000 6.000 6.000
Pr(> chisq) 1 0.00002 0.00002 0.00002 0.00002 0.00002
1 vs 4
Statistic N Mean St. Dev. Min Pctl(25) Pctl(75) Max
pseudoDf 2 130.000 1.414 129 129.5 130.5 131
Test.Stat 1 35.581 35.581 35.581 35.581 35.581
Df 1 2.000 2.000 2.000 2.000 2.000
Pr(> chisq) 1 0.00000 0.00000 0.00000 0.00000 0.00000
Predictors of total infarct growth
HIR Higashida Reperfusion
NIHSS on admission 1.146*** (0.253) 1.064*** (0.238) 1.536*** (0.271)
t = 4.530 t = 4.468 t = 5.671
p = 0.00002 p = 0.00002 p = 0.00000
IV tPA (yes) 0.052 (2.774) 0.557 (2.688) 0.652 (3.062)
t = 0.019 t = 0.207 t = 0.213
p = 0.986 p = 0.837 p = 0.832
Recanalization (partial) -1.135 (4.278) -0.057 (3.656) 6.325* (3.411)
t = -0.265 t = -0.016 t = 1.854
p = 0.792 p = 0.988 p = 0.067
Recanalization (full) -0.028 (4.646) -0.262 (3.923) -2.898 (5.167)
t = -0.006 t = -0.067 t = -0.561
p = 0.996 p = 0.947 p = 0.576
HIR 17.653* (10.182)
t = 1.734
p = 0.086
Higashida (poor) 9.345** (4.001)
t = 2.335
p = 0.022
Reperfusion 0.004 (0.016)
t = 0.271
p = 0.787
Circulation (posterior) 1.295 (2.850) 0.503 (2.717) 1.360 (3.210)
t = 0.454 t = 0.185 t = 0.424
p = 0.651 p = 0.854 p = 0.673
Recanalization (partial)*HIR 2.813 (13.503)
t = 0.208
p = 0.836
Recanalization (full)*HIR -10.734 (14.885)
t = -0.721
p = 0.473
Recanalization (partial)*Higashida (poor) 4.994 (5.807)
t = 0.860
p = 0.392
Recanalization (full)*Higashida (poor) -4.928 (5.757)
t = -0.856
p = 0.394
Recanalization (partial)*Reperfusion -0.099*** (0.019)
t = -5.302
p = 0.00000
Recanalization (full)*Reperfusion 0.002 (0.053)
t = 0.043
p = 0.966
Constant 1.133 (3.254) 1.265 (2.969) 2.635 (3.235)
t = 0.348 t = 0.426 t = 0.814
p = 0.729 p = 0.671 p = 0.417
Observations 141 141 138
R2 0.257 0.301 0.579
Adjusted R2 0.212 0.259 0.552
Residual Std. Error 14.158 (df = 132) 13.483 (df = 132) 16.086 (df = 129)
Note: p<0.1; p<0.05; p<0.01

Predictors of collateral flow defined by Higashida score

Dependent variable:
higashida_D1_bin
NIHSS_ad 0.038 (0.035)
t = 1.093
p = 0.275
age 0.003 (0.016)
t = 0.204
p = 0.839
sexMale 0.754* (0.407)
t = 1.852
p = 0.065
TSI -0.022 (0.028)
t = -0.793
p = 0.428
DWIvol_d1 0.081*** (0.020)
t = 3.974
p = 0.0001
circulationPosterior -0.018 (0.432)
t = -0.042
p = 0.967
Constant -1.855 (1.242)
t = -1.494
p = 0.136
Observations 186
Note: p<0.1; p<0.05; p<0.01

Predictors of collateral flow defined by HIR

Dependent variable:
HIR1
NIHSS_ad 0.038 (0.030)
t = 1.256
p = 0.210
age 0.012 (0.014)
t = 0.820
p = 0.412
sexMale 0.104 (0.373)
t = 0.278
p = 0.781
TSI -0.015 (0.027)
t = -0.560
p = 0.576
DWIvol_d1 0.008 (0.006)
t = 1.166
p = 0.244
circulationPosterior -0.143 (0.429)
t = -0.334
p = 0.739
Constant -2.071* (1.149)
t = -1.803
p = 0.072
Observations 186
Note: p<0.1; p<0.05; p<0.01